Digital media playback capabilities may be incorporated into a wide range of devices, including digital televisions, including so-called “smart” televisions, set-top boxes, laptop or desktop computers, tablet computers, digital recording devices, digital media players, video gaming devices, cellular phones, including so-called “smart” phones, dedicated video streaming devices, and the like. Digital media content (e.g., video and audio) may originate from a plurality of sources including, for example, over-the-air television providers, satellite television providers, cable television providers, online media services, including, so-called streaming services, and the like. Digital media content may be transmitted from a source (e.g., an over-the-air television provider) to a receiver device (e.g., a digital television) according to a transmission standard. Examples of transmission standards include Digital Video Broadcasting (DVB) standards, Integrated Services Digital Broadcasting Standards (ISDB) standards, and standards developed by the Advanced Television Systems Committee (ATSC), including, for example, the ATSC 2.0 standard. The ATSC is currently developing the so-called ATSC 3.0 standard.
In addition to defining how digital media content may be transmitted from a source to a receiver device, transmission standards may define how data may be transmitted to support so-called second screen applications. Second screen applications may refer to applications operating on a device other than a primary receiver device. For example, it may be desirable for a tablet computer to run an application in conjunction with the media playback on the primary media rendering device, where the application enables an enhanced viewing experience. Current techniques for enabling second screen applications may be less than ideal.